Method and apparatus for burning combustible liquids within a confined burning area

ABSTRACT

Oil residues and emulsions floating on a body of water are burned by confining the layer of residue within a furnace chamber. The furnace has combustion air inlet means adjacent the upper surface of the residue and a stack with inlets for a combustible gas. The combustible gas burns the combustible material in the gasses evolved from the combustion of the liquid residue to provide a relatively smokeless combustion process. The furnace is fabricated from a refractory material having insulating properties so that a substantial portion of the heat given off by the combustion of the residue is retained within the furnace to propogate further combustion of the residue and aid in the complete combustion of the difficult to burn portions of the residue. The furnace is preferably fabricated from a material that permits the furnace to float partially submerged in the body of water and may be easily transported from one location on the body of water to another location thereon. The furnace may be supported from suitable pilings and the residue conveyed directly into the furnace chamber. For certain types of difficult to burn residues, a layer of cellular glass nodules with a textured outer surface is positioned to float on the upper surface of the residue within the furnace chamber.

United States Patent [15] 3,695,810 Heagler Oct. 3, 1970 METHOD ANDAPPARATUS FOR I BURNING COMBUSTIBLE LIQUIDS [57] ABSTRACT WITHIN ACONFINED BURNING AREA [72] Inventor: Richard B. Heagler, Salem Tsh.,

Westmoreland County, Pa. [73] Assignee: Pittsburgh Corning Corporation,

Pittsburgh, Pa. [22] Filed: Nov. 17, 1970 [2]] Appl. No.: 90,348

[52] US. Cl. ..431/2, 431/298, 431/7 [51] Int. Cl ..F23d 21/00 [58]Field of Search ..431/2, 4, 7, 170, 298, 326, 431/331, 356; 110/7 R, 8R, 8 A, 8 C

[56] References Cited UNITED STATES PATENTS 3,403,645 10/1968 Flowers,Jr ..l 10/8 R X 3,556,698 l/197l Tully ..431/2 3,589,844 6/1971 Kraemer..431/2 X 2,246,346 6/1941 Carroll ..431/298 Primary Examiner-FrederickL. Matteson Assistant Examiner--W. C. Anderson Att0rney-Stanley J.Price, Jr.

Oil residues and emulsions floating on a body of water are burned byconfining the layer of residue within a furnace chamber. The furnace hascombustion air inlet means adjacent the upper surface of the residue anda stack with inlets for a combustible gas. The combustible gas burns thecombustible material in the gasses evolved from the combustion of theliquid residue to provide a relatively smokeless combustion process. Thefurnace is fabricated from a refractory material having insulatingproperties so that a substantial portion of the heat given off by thecombustion of the residue is retained within the furnace to propogatefurther combustion of the residue and aid in the complete combustion ofthe difficult to burn portions of the residue. The furnace is preferablyfabricated from a material that pemiits the furnace to float partiallysubmerged in the body of water and may be easily transported from onelocation on the body of water to another location thereon. The furnacemay be sup ported from suitable pilings and the residue conveyeddirectly into the furnace chamber. For certain types of difficult toburn residues, a layer of cellular glass nodules with a textured outersurface is positioned to float on the upper surface of the residuewithin the furnace chamber.

BACKGROUND OF THE INVENTION ficult to burn fractions and emulsions areundesirable j by-products. In the past, the emulsions have beencollected in settling pits adjacent the wells where the water isseparated from the crude oil. At predetermined intervals, highlycombustible liquids are added to the settling pits and the lighterfractions of the crude oil in the emulsions are burned. The heavier,more difficult to burn fractions remain as an incombustible materialwithin the settling pits. The heavy fractions frequently containsubstantial amounts of inorganic material such as drilling clays and thelike. During the combustion of the lighter fractions floating on thesurface of the water in the settling pits, a substantial amount ofdense, black smoke is generated. Because of the air polution problem andthe non-combustiblity of the residue heavy fractions, other meansandprocesses arebeing considered to dispose of the emulsions anddifficult to burn residues.

SUMMARY OF THE INVENTION In the present invention, a method andapparatus is provided for the substantially complete and relativelysmokefree burning of the combustible liquids within a furnace chamber.The furnace is fabricated from a refractory material having insulatingproperties to retain a substantial portion of the heat evolved duringcombustion within the furnace chamber. Combustion air inlet means areprovided into the furnace chamber adjacent the upper surface of theresidue. The furnace also includes apparatus for the combustion ofcombustible material in the gasses evolved from thecombustion of theliquid residue. The furnace may be fabricated from a material thatpermits the furnace to,

float on a body of water and confine the combustion of the liquidresidue to an area within the furnace chamber. For certain difficult toburn residues, a layer of cellular ceramic nodules are positioned tofloat on the upper surface of the residue within the furnace chamber.The cellularglass nodules preferably have a treated surface thatimproves the burning of the residues.

Accordingly, the principal object of this invention is to provide amethod and apparatus for the substantially complete combustion ofdifficult to burn liquids in a confined area.

Another object of this invention is to provide a method and apparatusfor burning difficult to burn combustible liquids without adding highlycombustible diluents to maintain combustion of the difficult to burncombustible liquids.

These and other objects and advantages of this invention will be morecompletely disclosed and described in the following specification, theaccompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view,partially in section, of one embodiment of the furnace floating on thesurface of a body of water having a layer of difficult to burncombustible material floating thereon.

FIG. 2 is a view in vertical section of the furnace illustrated in FIG.1 with a layer of cellular ceramic nodules floating on the upper surfaceof the difficult to burn combustible material.

FIG. 3 is a view in vertical section of another embodiment of thefurnace wherein the furnace is suitably supported on pilings and thedifficult to burn combustible liquid is fed to the furnace chamberthrough con- -duits.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Throughout the specification,the term cellular ceramic nodules with an outer treated surface isintended to designate nodules prepared in accordance with the processdescribed in U. S. Pat. No. 3,354,024 from a pulverulent glassy materialand a cellulating agent or from other pulverulent materials as describedin U. S. Pat. No. 3,441,396. A description of the process for treatingthe nodule surface by providing a textured surface may be found in U. S.Patent NO. 3,493,218. The cellular ceramic nodules enhance thecombustion of the combustible liquid floating on the surface of the bodyof water in accordance with the process described in copending U. S.Pat. No. application Ser. No. 829,746, and copending U. S. Pat.application Ser. No. 38,868. Other processes to improve the combustionenhancing properties of cellular glass nodules are described incopending U. S. applications Ser. No. 38,866 and Ser. No. 38,865. Thecellular ceramic nodules preferably have an apparent density of betweenabout 6 and 30 pounds per cubic foot and a thermal conductivity ofbetween about 0.40 and 0.50 Btu/hr./sq.ft./F.lin. at 75 F. For use as acombustion enhancing material, it is preferred that the nodules have asize of between A; and A inch with an apparent density of between 10 and20 pounds per cubic foot.

Referring to the drawings and particularly to FIGS. 1 and 2, there isillustrated one embodiment of the furnace generally designated by thenumeral 10. The furnace 10 is preferably fabricated from a mixture ofconcrete and cellular glass nodules so that the furnace will floatpartially submerged in a body of water. The furnace 10 has a pluralityof concentric rings 12, 14, 16, 18, 20 and 22 positioned in overlyingrelation with each other. The rings 12, 14, 16, 18, 20 and 22 arepreferably fabricated from an admixture of nodules and Portland cementin a weight ratio of 5:1. A typical furnace having a total height of 25inches, a bottom open-' ing of 26 inches and a top opening of 10 inches,weighs approximately pounds with an average wall thickness of 4 inches.Where desired, suitable reinforcing wires may be used on the lowermostrings. Also where desired, the top rings may be fabricated from anadmixture of cellular glass nodules and asphalt as a binder.

opening 28 are illustrated as extending radially through the ring 16, itis preferred that the air passages 26 and opening 28 for blower 30extend angularly to the radius to provide a circular motion for the airentering the chamber 24. With this arrangement, during combustion withinthe chamber 24, combustion air is drawn into the chamber 24 through theair passages 26 and,

where it is desired, the blower 30 provides air under pressure throughopening 28 to the furnace chamber 24 adjacent the top surface 32 of theliquid within the chamber 24. Suitable inlet openings 34 may also beprovided in the top ring 22 for conduits 36 that are connected to asource of combustible gas such as methane, or the like. The openings 34in the top ring 22 are arranged to provide for combustion of thecombustible materials in the gasses evolved during the combustion of theliquid within the chamber 24 to provide relatively smoke-free combustiongasses.

As illustrated in FIG. 2, where the layer of combustible liquid isdifficult to burn and where complete combustion of the combustibleliquid is desired, a layer of cellular ceramic nodules 38 may bepositioned in the chamber 24 to float on the upper surface of thecombustible liquid and enhance the combustion of the combustible liquidin the manner noted in the above mentioned copending U. S. applications.

The furnace is positioned on a body of water 40 to float thereon with aportion of the furnace submerged below the upper surface 32. Thedifficult to burn combustible liquid is lighter than water and floats onthe upper surface 32. To ignite the combustible liquid, a small amountof a primer such as Varsol or other suitable low flash point ignitingagent, is poured onto the surface 32 and is ignited by any suitablemeans It should be understood that the furnace 10 could include anautomatic or remotely controlled resistance type igniter or the like toignite the liquid on the surface 32. After the combustible liquid isignited combustion continues until substantially all of the combustibleliquid within the confines of the chamber 24 floating on the surface ofthe water 40 is burned. Little, if any, residue remains. Since thefurnace 10 is floating on the body of water 40, it may be easily movedor transported thereon by any suitable means to be positioned with a newinventory of the combustible material within the chamber 24. v

The furnace 10 being fabricated from Portland cement and cellular glassnodules has refractory ,properties in that a minimum of spalling occurswithin the furnace chamber during the combustion of the combustibleliquid. Also, the nodule-concrete mixture provides insulating propertiesfor the furnace 10 so that the heat I generated during the combustion ofr the combustible liquid is retained within the chamber 24 and it isbelieved, contributes to the substantially complete comwithin thechamber 24. With the furnace 10, it is now possible to confine thecombustion to the circumferential area of the'chamber24 and tosubstantially and completely burn the combustible liquid floating on thesurface of the body of water 40 with a generally smokeless flame.Although the configuration of the floating furnace 10 is generallydescribed as circular,

formed from a plurality of rings, it should be un-.

derstood that the furnace may have other configurations, as, forexample, rectangular or a poly-sided pyramidal shape.

Referring to FIG. 3, another embodiment of the furnace is illustratedand generally designated by the number 50. The furnace includes a basering member 52 with an intermediate section 54 formed in the shape of aconical segment and an upper cylindrical stack section 56. The furnace50 is preferably supported on a plurality of vertical posts or pilings58. Air passages 64 are provided in the intermediate section 54 and,where desired, a blower similar to blower 30 may also be provided. Thestack 56 has passages 66 for secondary combustion gas conduits 68. i

There are illustrated a pair of combustible liquid supply conduits 70and 72. The conduit 70 has an outlet opening 74 beneath the chamber 76of furnace 50. The conduit 70 is located below the surface 78 below thebody of water 80 and has an outlet opening 74 below the surface 78 andbeneath the chamber 76. With this arrangement, combustible liquid flowsout of conduit 70 through outlet opening 74 and floats upwardly in thebody of water 80 to the surface 78 where it is ignited and burned, aspreviously discussed.

An alternate conduit 72 opens through the wall of the furnaceintermediate portion 54 and has an outlet opening 82 through which thecombustible. liquid flows into the chamber 76. A suitable flap valve 84is provided to close the outlet opening 82 during the combustion of thecombustible liquid. A valve 86 is positioned in conduit 72 to controlthe flow of combustible liquid into the chamber 76.

The combustion of the combustible liquid within the chamber 76 issubstantially the same as that previously described. The sections 52, 54and 56 'of furnace 50 may also be fabricated from cellular glass nodulesand Portland cement to provide the desirable insulating and refractoryproperties. Other materials, however, may be employed. It is desirable,however, that the furnace haveinsulating properties to retain asubstantialpon tion of the heat generated by the combustion gasseswithin the furnace chamber to contribute to the complete combustion ofthe combustible liquid.

The following examples are illustrative of the combustion of variousdifficult to burn combustible liquids floating onthe surface of a bodyof water. A furnace similar to the furnace illustrated in FIGS. 1 and 2was positioned to float on a body of water havinga depth ofapproximately-2 feet and a diameter of approximately l 0fee t. I r gEXAMPLEI the surface of the water within the furnace chamberfAmono-layer of cellular ceramic nodules was positioned clear, without anyevidence of oil being present thereon. I

EXAMPLE II A similar test was performed with settling pit residue fromVenice, Louisiana that contained about 55 percent by weight water andsome drilling clays. The water formed an emulsion with the oil. Twoquarts of this emulsion were poured onto the upper surface of the waterwithin the furnace chamber. Again, cellular ceramic nodules were appliedas a mono layer on the liquid surface within the furnace chamber. 100c.c. of a low flash point primer was poured onto the liquid surfacewithin the furnace chamber and ignited. The burn was relatively completewith very little smoke. The water within the chamber was clear. Therewas, however, a slight residue adhering to the cellular ceramic nodules.

EXAMPLE III A residual oil from Louisiana, taken from a settling pit inwhich the residual had aged for a period of approximately 23 years andcontaining 40 percent Bentonite clay by weight and percent water byweight, was burned in a similar manner within the furnace chamber. Thisresidual material burned less readily than the material discussed inExamples I and II. Toward the end of the burn, an air blower injectedair, under pressure, through one of the air passages and the burnincreased in intensity. After the burn was completed, the water wasclear and clean and the nodules were substantially free of residue.

EXAMPLE IV Another burn was accomplished with the residual material setforth in Example III with the air blower on during the entire burn. Anintense, hot flame was produced with little .smoke throughout the burn.After the burn the water was clean and the nodules showed little or noresidue adhering thereto.

EXAMPLE V point primer added. The oil ignited and little or no smoke waspresent. After combustion was completed, the water was clear, withoutevidence of oil.

EXAMPLE VI The burning procedure described in Example I was repeatedwith aMississippi-Louisiana crude oil having an A.P.I. gravity of 39.040.5, a sulfur content of between 0.2 percent and 1 percent and anasphalt content of between 5 and 6 percent. The flash point wasindicated as ambient. The burn was complete with no residue remaining onthe surface of the liquid within the furnace chamber.

EXAMPLE VII The burning procedure described in Example I was repeatedwith Bunker C oil having a flash point of 200 The material of ExampleIII was burned under the same conditions as Example IV without a layerof cellular ceramic nodules on the surface of the liquid within thechamber. A larger amount of smoke was generated during the combustion ascompared with Example III. After a period of time, combustion stoppedand an inspection of the liquid surface within the chamber indicated oilremaining on the surface of the water. Additional low flash point primerwas added and ignited and combustion continued for a relatively shortperiod of time. The addition of primer was again repeated, however, uponcompletion of the burn, it was noted thatoil remained on the surface ofthe liquid. Thereafter, a monolayer of cellular ceramic. nodules wasplaced on the liquid surface within thev chamber and a low flash F. andan A.P.I. gravity of between 13 and 15. The sulfur content was 6 percentand the asphalt content was between 55-60 percent. The burn was completewithout any oil residue remaining; on the surface of the water.

In order to further reduce the smoke, the cellular ceramic nodules weresprayed with a 10 percent solution of barium petrasol, a smoke reducingagent used in Diesel fuels. The addition of the barium petrasol furtherreduced the smoke generated during combustion.

Although cellular ceramic nodules enhance the combustion of the abovedifficult to burn combustible materials, it is possible, withoutnodules, to burn relatively difficult toburn combustible materials,although not completely, in the previously described furnace chambers ona body of water and to isolate the combustion area.

According to the provisions of the patent statutes, I have explained theprinciple, preferred construction and mode of operation of my inventionand have illus trated and described what I now consider to represent itsbest embodiments. However, I desire to have it understood that, withinthe scope of the appended claims, the invention may be practicedotherwise than as specifically illustrated and described.

lclaim:

1. Process for burning a combustible liquid within a confined areacomprising,

confining a combustible liquid within a furnace chamber, positioning alayer of cellularceramic nodules on said combustible liquid surface,

supplying combustion air to said chamber at a location adjacent to theupper surface of said combustible liquid,

igniting said combustible liquid on the surface of said cellular ceramicnodules,

. retaining a substantial portion of the heat generated by thecombustion of said combustible liquid within said chamber to propagatethe further combustion of said combustible liquid,

withdrawing the gasses of combustion from said chamber through a stackoutlet opening abovethe top surface of said liquid, and

burning substantially all of said combustible liquid in said chamber.

2. A process for burning a combustible liquid within a confined area asset forth in claim 1 which includes,

adding a primer liquid having a flash point substantially lower thansaid combustible liquid to a portion of said combustible liquid surfacewithin said chamber, igniting said primer liquid and said combustibleliquid within said chamber. 3. A process for burning a combustibleliquid within a confined area as set forth in claim 1 which includes,

supplying a combustion gas to said chamber adjacent said stack outletopening, burning combustible material in said combustion gas adjacentsaid stack outlet opening and withdrawing substantially smoke-free gasesfrom said combustion chamber through said stack outlet. 4. A process forburning a combustible liquid within a confined area as set forth inclaim 1 which includes,

supplying combustion air under pressure to said chamber at a locationadjacent to the upper surface of said combustible liquid, andwithdrawing substantially smoke-free gases of combustion from saidchamber through said stack outlet. 5. A process for burning acombustible liquid within a confined area as set forth in claim 4 inwhich,

said combustible liquid comprises an oil-water emulsion containing up to55 percent water by weight. 6. A process for burning a combustibleliquid within a confined area as set forth in claim 4 in which,

said combustible liquid contains up to 40 percent by weight pulverulentclay products. 7. A process for burning a combustible liquid within aconfined area as set forth'in claim 1 in which, I

said combustible liquid floats as a layer on the upper surface of a bodyof water. 8. A process for burning a combustible liquid within aconfined area as set forth in claim 7 in which,

said furnace chamber has a bottom opening, and positioning said furnacechamber with said bottom opening below said layer of combustible liquidto isolate a portion of said combustible liquid layer within saidchamber. 9. A process for burning a combustible liquid within a confinedarea as set forth in claim 8 which includes,

floating said furnace on said body of water with said chamber openingbelow said layer of combustible liquid to isolate a portion of saidlayer of combustible liquid within said chamber. 10. A process forburning a combustible liquid within a confined area as set forth inclaim 8 which includes,

feeding combustible liquid to said chamber through a conduit having anopening below said layer of combustible liquid and in said body of waterand below said chamber bottom opening. 11. Apparatus for burning acombustible liquid within a confined area comprising,

- a furnace having a chamber with a bottom opening and a top outletopening, said furnace having walls of a refractory insulating materialto retain substantial portion of the heat generated by the combustion ofsaid combustible liquid within said chamber to further propagatecombustion of said combustible liquid within said chamber, air inletopenings in said furnace walls adjacent said bottomo ni ,a d said furnacb ig formed from a relatively light material so that said furnace floatspartially submerged on a body of water with said bottom opening belowthe upper surface of said body of water and said air inlet openingsabove said upper surface of said body of water.

12. Apparatus for burning a combustible liquid within a confined area asset forth in claim 1 l which includes,

means to supply air under pressure through said side walls into saidchamber.

13. Apparatus for burning a combustible liquid within a confined area asset forth in claim 12 which includes,

means to supply combustion gas adjacent to said out let opening to burncombustible material in the combustion gases evolved while burning saidcombustible liquid.

1. Process for burning a combustible liquid within a confined areacomprising, confining a combustible liquid within a furnace chamber,positioning a layer of cellular ceramic nodules on said combustibleliquid surface, supplying combustion air to said chamber at a locationadjacent to the upper surface of said combustible liquid, igniting saidcombustible liquid on the surface of said cellular ceramic nodules,retaining a substantial portion of the heat generated by the combustionof said combustible liquid within said chamber to propagate the furthercombustion of said combustible liquid, withdrawing the gasses ofcombustion from said chamber through a stack outlet opening above thetop surface of said liquid, and burning substantially all of saidcombustible liquid in said chamber.
 2. A process for burning acombustible liquid within a confined area as set forth in claim 1 whichincludes, adding a primer liquid having a flash point substantiallylower than said combustible liquid to a portion of said combustibleliquid surface within said chamber, igniting said primer liquid and saidcombustible liquid within said chamber.
 3. A process for burning acombustible liquid within a confined area as set forth in claim 1 whichincludes, supplying a combustion gas to said chamber adjacent said stackoutlet opening, burning combustible material in said combustion gasadjacent said stack outlet opening and withdrawing substantiallysmoke-free gases from said combustion chamber through said stack outlet.4. A process for burning a combustible liquid within a confined area asset forth in claim 1 which includes, supplying combustion air underpressure to said chamber at a location adjacent to the upper surface ofsaid combustible liquid, and withdrawing substantially smoke-free gasesof combustion from said chamber through said stack outlet.
 5. A processfor burning a combustible liquid within a confined area as set forth inclaim 4 in which, said combustible liquid comprises an oil-wateremulsion containing up to 55 percent water by weight.
 6. A process forburning a combustible liquid within a confined area as set forth inclaim 4 in which, said combustible liquid contains up to 40 percent byweight pulverulent clay products.
 7. A process for burning a combustibleliquid within a confined area as set forth in claim 1 in which, saidcombustible liquid floats as a layer on the upper surface of a body ofwater.
 8. A process for burning a combustible liquid within a confinedarea as set forth in claim 7 in which, Mu said furnace chamber has abottom opening, and positioning said furnace chamber with said bottomopening below said layer of combustible liquid to isolate a portion ofsaid combustible liquid layer within said chamber.
 9. A process forburning a combustible liquid within a confined area as set forth inclaim 8 which includes, floating said furnace on said body of water withsaid chamber opening below said layer of combustible liquid to isolate aportion of said layer of combustible liquid within said chamber.
 10. Aprocess for burning a combustible liquid within a confined area as setforth in claim 8 which includes, feeding combustible liquid to saidchamber through a conduit having an opening below said layer ofcombustible liquid and in said body of water and below said chamberbottom opening.
 11. Apparatus for burning a combustible liquid within aconfined area comprising, a furnace having a chamber with a bottomopening and a top outlet opening, said furnace having walls of arefractory insulating material to retain substantial portion of the heatgenerated by the combustion of said combustible liquid within saidchamber to further propagate combustion of said combustible liquidwithin said chamber, air inlet openings in saId furnace walls adjacentsaid bottom opening, and said furnace being formed from a relativelylight material so that said furnace floats partially submerged on a bodyof water with said bottom opening below the upper surface of said bodyof water and said air inlet openings above said upper surface of saidbody of water.
 12. Apparatus for burning a combustible liquid within aconfined area as set forth in claim 11 which includes, means to supplyair under pressure through said side walls into said chamber. 13.Apparatus for burning a combustible liquid within a confined area as setforth in claim 12 which includes, means to supply combustion gasadjacent to said outlet opening to burn combustible material in thecombustion gases evolved while burning said combustible liquid.